Control pedal assembly



y 1950 R. KRESS ETAL 2,516,397

CONTROL PEDAL ASSEMBLY Filed Dec. 7, 194a 1v 2 Sheets-Sheet 1 m FIG. I

, FIG 4 f3l INVENTOR.

RALPH KRESS K v1 BY GALE GRISWOLD A'TTORNEY July 25, 1950 ss r L 2,516,397

CONTROL PEDAL ASSEMBLY Filed Dec. '7, 1946 2 Sheets-Sheet 2 INVENTOR.

RALPH KRESS BY GALE GRISWOLD' @mw. 42m

A T TORNE Y Patented July 25, 1950 poration of. Delaware .assignors to Curtiss-Wright Corporation, a cor- I Application December 7, 1946, Serial No. 714,878

I t This invention relates. to an improved control pedal assembly for airplanes andother devices.

Objectives of the invention reside in the provision of an improved'assembly which has pedals arranged to accomplishudual 500111101 functions,

such as the operation of an'airplane rudder and wheel brakes; which maybe installedras a unit; which may be adjusted by a single operation to accommodate operators of difierent stature; and

which in all positions of adjustment or :operation maintains the pedals-properly aligned with the operators feet.

These and other objects and advantages of the invention will become apparent from the following description of the typical embodiment shown in the accompanying drawings, wherein: Figure 1 is a simplified diagrammatic plan view showing the relationship .of the control pedalassembly to the wheelbrakes and rudder plane;

Figures 2 and 3-are isometric views'of thecontrol pedal assembly taken from the frontand rear, respectively; and,

Figured is a longitudinal vertical sectional view of the assembly.

As shown in Figure .1 the control pedal assembly, indicated generally at It has .a'crank arm 1H pivotally connectedat I2' to a link I3. The latter is pivoted at M to horn 15 of. rudder 16, whereby upon swinging of arm vl I the rudder will be swung about the .axis H of its hinge connection to the aircraft. The pedal assembly likewise includes a pair of independently movable crank arms i8 and I9, each of which is connected by linkage 2| to an actuating cylinder 220i the brake system for one of the wheels23. The actuating cylindersone for the brake of each wheel pedal assembly HZ! includes a .base'ZB for attachment to a floor or other support indicated at 21 and provided with a .front depending tubular part 28 and a rear depending tubular part :29.

Part 28 rotatably supports an upright spindle 30 upon whose lower end .3! the crank arm 1.! is .aflixed. Rigid with and extending forwardly from the upper portion of spindle 30 is 'a'tubular of an air- .7. Claims. (Cl. 74-478) member 32 which supports a'plunger '33 for-telescoping movement. Arms 36 and .31 respectively have bifurcated ends 38 and 39 mounted on suitable bushings on the spindle 30 so that the-arms canswing about the upright spindle axis. A link 4| is pivoted at 42 .to arm 36 and at 43 toe-fitting on the forward end of plunger 33. A similar link 44 is pivoted at '45 to-armBl and at 43 to plunger 33.

Threaded to the plunger is a screw 46 whicr is mountedfor rotationi-n suitable bearingmeans carried by -member '32. A bevel gear 4'! keyed to the screw is driven by a second bevel .gear '48 rotatably mounted within a gear housing 49.

Gear 48 is driven by a flexible shaft '5l which extends through arlexible housing .52 and which has an operating crank handle 53. A fitting 54 .on'the end of housing 52 is adapted to support the handle 53 in'a location convenient .to the operator, as for example on or beneath the instrument panel in the case of an airplane.

The rear-depending tubular part 2-9 :of the base supports a fixed bearing tube 64in which is journalled a sleeve 65 thatin turn journals a'spindle .66. Secured to the lower ends of the members 65 and .66 areyrespectively, the brake operating arms =|-9 and I8; and secured to the'upper ends of these members are arms 6'! and 16B, respectively. Supported on tubeM, preferablyby antifriction-bearings is a sleeve 6'9 upon which in turn are--journalledthe bifurcated ends 'H and 12 of arms 13 and", respectively.

A right pedal support is pivoted at 116 to the outer end-of arm 36 and at 1-! to arm '13.

Likewise a left pedal support 18 is pivoted at 19 to arm 3'! and at 8! to'arm 14. Toeach-of' supports 15 and 18 there is hinged on a transverse axis at 82 a pedal 83. The pedals extend about pivots 82 and have depending arms 84 that are pivotally connected by short links '83 to bell crank members 85. The latter are mounted on the respective pivots l1 and 8| and are alsopivoted 83 willbe held properly aligned with the pilots "feet since the members 26,31, 14,13 and 26, 136, 13,15 constitute parallelogram linkages. 1 The formed by the axes of arms 36, 37 so that ad'--'- justment of the pedals to accommodate persons of longer or shorter leg length will in no wise afiect the neutral positicnof the rudder. Dur

ing such adjustment the pedals are always held properly aligned, i. e., parallel with the transverse axis of the airplane, by reason of the paral lelogram linkages heretofore pointed out.

For operating the brakes, the pedals 83 are swung forwardly about their pivots 82. With reference to Figure 2, it will be seen that such operation to the left pedal will move link 89 to the rear (to the right) causing bell crank 85 and arm 5? to move counterclockwise. This will cause arm 19 also to move counterclockwise, ap' plying the left wheel brake 25 as will be seen from Figure l. The parts i8, 66 and t8 together may be considered to constitute one brake control element, and the parts 9, 85 and 6? another such control element.

Adjustment of the pedals by turning handle 53 or rudder movement of the pedals will not afiect the brake system because the left linkage 6'1, 86, 85, I4 is also a parallelogram system, as is the'right linkage t8, 8'6, 85,13. Brake application can therefore be accomplished only by pushing pedal 83 forwardly about its transverse hinge axis 82. In Figure l the brake linkage appears in its operated position, with the arms l8, l9 and 5?, 88 diverging in order that the lowermost arm of each pair may be seen.

It will be understood that the control pedal assembly may be employed on various devices other than land, water and aircraft, since the pedals may be used for other purposes than directional and brake control if desired. It will also be understood that the assembly specifically shown and described is merely illustrative of the inventive principles involved, and that these principles may be otherwise embodied without departing from the spirit of the invention or from the scope of the appended claims.

We claim:

1. In a control pedal assembly, a base, a pair of pedal supports each having a pedal mounted thereon for tilting movement, a parallelogram linkage for each pedal support connecting it to the base upon substantially upright pivot axes for fore and aft movement relative thereto, ad-

justable means connecting the parallelogram linkages for adjusting the pedals in a fore and aft direction, a pair of control elements, and a control linkage connecting each pedal with one of said control elements, said control linkage together with said parallelogram linkage defining a second parallelogram linkage system whereby only tilting movement of the pedals will efiect movement of the control elements.

2. In a control pedal assembly, a base having afirst, second and third control elements pivoted thereto, first and second arm means pivoted intermediate the ends thereof to said base, a pedal support on each side of the base pivoted to the arm means adjacent the ends thereof, each support and the arm means defining with the base a parallelogram system, a member pivoted to each support, a link pivotally connecting one member with the second control element and a link pivotally connecting the other member withthe third control element, each link and member together with the associated arm means and control member constituting a parallelogram system, a pedal mounteu me ch support for movement relative thereto, and means for translating such movement of each pedal into relative movement of the associated member and support.

3. In a control pedal assembly, a base having first, second and third control elements pivoted thereto, first'and second sets of arms pivoted to said base on spaced axes, each set comprising two arms extending oppositely to each other laterally of the base, a pedal support on each side of the base pivoted to the arms extending to that side, each support and tl'ie arms pivoted thereto defining with the basef a parallelogram linkage system, a member pivoted to each support, a link pivotally connecting one member with the second control element and a link pivotally connecting the other member with the third control element, each link and member together with the associated arm and control member constituting a parallelogram linkage system, a pedal mounted for movement on each support, means for translating such movement of each pedal into relative movement of the associated member and support, and means for adjusting the angular relation of the arms to the first control element.

4. In a control pedal assembly, a base having a first control element pivoted thereto on a first substantially upright axis, second and third control elements pivoted to the base on a second axis substantially parallel the first axis, first and second sets of arms pivoted to said base on said first and second axes respectively, each set comprising two arms extending oppositely to each other laterally from the base, a pedal support on each side of the base pivoted to the arms extending to that side, a member pivoted to each support substantially coaxially with the pivot thereto of the arm of the second set, alink pivotally connecting one member with the second control element and a link pivotally connecting the other member with the third control element, a pedal mounted movably on each support, means for translating such movement of each pedal into relative movement of the associated member and support, and means for adjusting the angular relation of the arms of the first set to the first control element.

5. In a control pedal assembly, a base having a first control element pivoted thereto on a first substantially upright axis, second and third control elements pivoted to the base on a second axis parallel the first axis, first and second sets of arms pivoted to said base on said first and second axes respectively, each set comprising two arms extending oppositely to each other laterally from the base, a pedal support on each side of the :base pivoted to the arms extending to that side, each support and the arms pivoted thereto defining with the base a parallelogram system, a member pivoted to each support substantially coaxially with the pivot thereto of the arm of the second set, a link pivotally connecting one member with the second control element and a link pivotally connecting the other member with the third control element, each link and its member together with the associated arm and control element constituting a parallelogram system, a pedal mounted on each support for pivotal movement about a substantially transverse axis, means for translating pivotal movement of each pedal into relative movement of the associated member and support, and means for simultaneously adjusting the angular relation of both arms of the first set to the first control element.

6. In an aircraft rudder and brake control pedal assembly, the aircraft having a rudder control element pivoted thereto on a first substantially upright axis, two brake control elements pivoted to the base on a second axis parallel the first axis, first and second sets of arms pivoted to said base on said first and second axes respectively, each set comprising two arms extending oppositely to each other laterally from the base, a pedal support on each side of the base pivoted to the arms extending to that side, each support and the arms pivoted thereto defining with the base a parallelogram system, a member pivoted to each support substantially coaxially with the pivot thereto of the arm of the second set, a link pivotally connecting one member with one brake control element and a link pivotally connecting the other member with the other brake control element, each link and member together with the associated arm and brake control element constituting a parallelogram system, a pedal mounted on each support for pivotal movement about an axis substantially transverse of the aircraft, means for translating pivotal 30 movement of each pedal into relative movement of the associated member and support, and means for simultaneously adjusting the angular rela- 6 tion of both arms of the first set to the rudder control element.

'7. In a control pedal assembly, a base, a pedal support and a pedal mounted for tilting movement on the support, parallel links pivotally connected upon substantially upright pivot axes to the support and to the base and defining therewith a parallelogram linkage system, a control element pivotally mounted on the base, and a control linkage connecting said pedal and pedal support and control element, said control linkage together with one of said parallel links defining a second parallelogram linkage system whereby only tilting movement of the pedal will effect movement of the control element relative to the base.

RALPH KRESS. GALE GRISWOLD.

REFERENQES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Great Britain Sept. 10, 1940 

